1. Field of the Invention
This invention relates to an adaptive coupling mechanism, and in particular to a coupling mechanism arranged to replace a conventional threaded coupling ring or nut. The adaptive coupling mechanism of the invention enables linear push-pull quick coupling and decoupling of a first connector half to and from an externally threaded mating connector half. In addition, the adaptive coupling mechanism of the invention includes anti-decoupling features that prevent the connector halves from being unintentionally decoupled as a result of shocks or vibrations.
The coupler of the invention may be used in electrical, hydraulic, or pneumatic coupling systems, and in a preferred embodiment, includes a multi-tined locking ring that, following initial axial insertion, engages the mating threads of the externally threaded connector half with a series of locking tines. A coupling sleeve is biased in a first direction to a locking position in order to prevent unintentional decoupling, and is arranged to be pulled in a second direction opposite the first direction to permit axial disengagement of the locking tines from the threads of the threaded connector half and thereby permit axial decoupling. The tines are arranged to permit some rotation in order to prevent breakage due to improper operation.
2. Description of Related Art
Conventional threaded coupling systems are composed of two coupling halves. The first coupling half has mounted on it a rotatable coupling ring or nut having an internally threaded diameter, and the second coupling half is externally threaded to accept and rotatably mate with the internally threaded coupling ring or nut of the first coupling half.
By way of example, some electrical connectors employ a coupling system that is threaded at a pitch of 20 threads per inch, and are mated together by rotation of the internally threaded coupling ring onto the externally threaded connector half. Typically, such coupling systems require from a half to a full dozen turns to bring the connectors to a full mate.
In order to avoid the need to rotate the internally threaded coupling ring onto the externally threaded connector half, a number of connector designs exist which replace the coupling ring with push-pull type "quick connect/disconnect" mechanisms or structures. For the most part, these designs are in the form of systems that completely replace both the internally and externally threaded portions of the rotatable coupler with a linear coupling mechanism that may consist of detented tines, complementary structures arranged to form an interference fit, and more complicated latching structures.
In existing systems, it is generally impractical to completely replace all male and female couplers. As a result, if the rotational coupling system is to be replaced by a push-pull system, some type of adapter is needed. An example of such an adapter was proposed many years ago in the related context of lighting systems, to permit quick connection and disconnection of light bulbs from their sockets. Examples of this concept are described in U.S. Pat. Nos. 1,721,365, 3,173,473, and 5,380,214, each of which discloses an adapter ring for a light socket that permits axial push-pull engagement and disengagement of tines from conventional externally threaded light bulbs.
A problem with the light socket designs, which makes them inapplicable to many electrical, pneumatic, or hydraulic coupler applications, is that the adapters disclosed in these patents do not include any provision for preventing unintentional release of the threaded portion of the light bulb from its mating socket. This is a serious disadvantage in, for example, military or aerospace applications where the adapter is subject to shocks and vibrations that could cause the threads to disengage or pull away from the tines, leading to risks of electrical shock in the case of electrical power connectors, leakage in the case of hydraulic connection systems, or failure of the equipment being coupled.
An improvement over the push-pull designs used in the context of lighting systems, which provides for push-pull engagement of a coupler mechanism with a threaded connector half and also provides for positive anti-vibration or decoupling prevention, is the coupling mechanism disclosed in U.S. Pat. No. 4,941,846. This coupling mechanism uses a cam arranged to cause internally threaded coupling jaws to engage the external threads of a mating connector half as the coupling mechanism is pushed onto the connector half, and a coupling sleeve that extends over the jaws to prevent their disengagement from the mating coupler half until the sleeve is pulled back.
A disadvantage of the coupling mechanism disclosed in U.S. Pat. No. 4,941,846 is that, while the use of a cam and internally threaded jaws permits axial engagement and disengagement of the coupling mechanism to and from the externally threaded connector half, the arrangement is relatively costly in comparison with alternative conventional rotational or push-pull type coupler systems, and is difficult to adapt to most existing connector systems.
A final group of prior coupling mechanisms involving adapters fitted onto externally threaded connector halves is disclosed in U.S. Pat. Nos. 3,430,184, 3,452,316, 4,208,082, and 4,632,480. The coupling mechanism in this group share structures with those of the push-pull light socket adaptors and the coupling mechanism of U.S. Pat. No. 4,941,846, but are used in the context of quick-release umbilical chord connectors for missiles, bombs, and the like, and thus are designed only to facilitate axial disengagement rather than both axial coupling and decoupling.
To date, the inventors are aware of no other prior coupling mechanism that offers the combination, provided by the invention, of a coupling mechanism that can mate and lock a first connector half to a second externally threaded connector half using a purely linear motion, that also permits linear disengagement of the mating connector halves as well as positive decoupling prevention, and yet that can economically be provided either as an integrated connector/coupler half or as an adaptor for an existing connector or coupler half.